ARM project manager Kevin Weinert called the technologies “definitely momentous,” both for the public and the aircraft industry. Weinert is at NASA Armstrong in Southern California.

“While there are obvious potential economic gains for the industry,” Weinert said in a statement, “this benefits the people who live near major airports and have to deal with the noise of aircraft coming in to land.”

Three technologies were tested in a series of flights conducted 350 feet above a dry lake bed at Edwards Air Force Base, adjacent to NASA Armstrong. The test flights concluded in May, and NASA announced the results last week.

Two technologies involve the landing gear and the noises made when air moves past the landing gear upon approach to a runway, and when it gets pulled into the airframe cavity after the gear is deployed.

NASA just completed test flights of Acoustic Research Measurement (ARM) technologies that can reduce airframe noise produced during landing by more than 70 percent. Here, a porous fairing on landing gear is one technology. (NASA / Ken Ulbrich / HANDOUT)

Langley engineers addressed the first issue by devising porous fairings with tiny, strategically placed holes that allow air to flow through while also deflecting some of it around the landing gear. Fairings are structures placed over gaps in an aircraft to smooth out the shape and reduce drag.